2,512 research outputs found

    Characterization of the dry bean polygalacturonase-inhibiting protein (PGIP) gene family during Sclerotinia sclerotiorum (Sclerotiniaceae) infection.

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    Polygalacturonase-inhibiting proteins are leucine-rich repeat proteins that inhibit fungal endopolygalacturonases. The interaction of polygalacturonase-inhibiting protein with endopolygalacturonases limits the destructive potential of endopolygalacturonases and may trigger plant defense responses induced by oligogalacturonides. We examined the expression of fungal pg and plant Pvpgip genes in bean (Phaseolus vulgaris) stems infected with Sclerotinia sclerotiorum to determine whether any of them are associated with the infection process. Transcriptional analysis was carried out by means of semi-quantitative reverse transcription PCR or real-time PCR. The sspg1 gene was highly expressed during infection; sspg3 was regulated during the later phases of infection; sspg5 was more uniformly expressed during infection, whereas sspg6 was only weakly expressed. During the course of infection, Pvpgip1 transcripts were not detected at early stages, but they appeared 72 h post-inoculation. High levels of Pvpgip2 expression were observed during the initial phase of infection; the transcript peaked by 48 h post-inoculation and declined by 72 h post-inoculation. Pvpgip3 expression increased strongly at 96 h post-inoculation. Pvpgip4 was constantly present from 24 h post-inoculation until the end of the experiment. However, we detected higher levels of the Pvpgip4 transcript in the necrotic lesion area than in plants that had been mechanically wounded. Remarkably, only Pvpgip4 appeared to be moderately induced by mechanical wounding. These results provide evidence that endopolygalacturonases contribute to the infection process during host colonization by promoting the release of plant cell oligogalacturonides, which are powerful signaling molecules and may also activate plant defenses, such as polygalacturonase-inhibiting proteins

    Mineração em metadados aplicados ao processo de desenvolvimento de coleções

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    The increasing of the new scientific areas, along with the multitude of information items, it's pushing the librarians to find creatively novel ways to gather information for the development of the collection under their responsability. This must definitely change the usual practice of these professionals towards mastering moderns IT tools in order to better analyse a huge volume of data in a shorter amount of time. Hence, this paper discusses a proposal of building metadata of the syllabus plans, within a university to easy the minering some important information out of them as part of a master collection development policy

    Avaliação de sistema de produção alternativo para feijão com uso de fungicidas.

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    Combining unsupervised and supervised neural networks in cluster analysis of gamma-ray burst

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    The paper proposes the use of Kohonen's Self Organizing Map (SOM), and supervised neural networks to find clusters in samples of gammaray burst (GRB) using the measurements given in BATSE GRB. The extent of separation between clusters obtained by SOM was examined by cross validation procedure using supervised neural networks for classification. A method is proposed for variable selection to reduce the "curse of dimensionality". Six variables were chosen for cluster analysis. Additionally, principal components were computed using all the original variables and 6 components which accounted for a high percentage of variance was chosen for SOM analysis. All these methods indicate 4 or 5 clusters. Further analysis based on the average profiles of the GRB indicated a possible reduction in the number of clusters

    Características físico-químicas de sucos de uvas Isabel Precoce e BRS Violeta elaborados no Nordeste do Brasil.

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    A avaliação da adaptação de variedades de uva destinadas à elaboração de sucos a determinadas condições de clima e solo requer estudos específicos, contando com uma avaliação analítica do produto elaborado. O objetivo do presente trabalho foi comparar os sucos obtidos a partir de duas variedades de uvas labruscas produzidas no Vale do São Francisco. Os sucos foram elaborados em triplicata pelo método artesanal, a partir de uvas das variedades BRS Violeta e Isabel Precoce. As variáveis analisadas foram pH, sólidos solúveis totais, acidez total e volátil, dióxido de enxofre livre e total, teor alcoólico, índice de cor, antocianinas totais e índice de polifenóis totais (I-280). As médias foram comparadas pelo teste de Tukey a 5% de probabilidade. Apenas para o pH não houve diferença significativa, sendo as demais variáveis significativamente diferentes entre as variedades, nos sucos analisados. A variedade BRS Violeta apresentou excelente potencial para a elaboração comercial de sucos na região

    Small inner marsh area delimitation using remote sensing spectral indexes and decision tree method in southern Brazil

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    Revista oficial de la Asociación Española de Teledetección[EN] Vast small inner marsh (SIM) areas have been lost in the past few decades through the conversion to agricultural, urban and industrial lands. The remaining marshes face several threats such as drainage for agriculture, construction of roads and port facilities, waste disposal, among others. This study integrates 17 remote sensing spectral indexes and decision tree (DT) method to map SIM areas using Sentinel 2A images from Summer and Winter seasons. Our results showed that remote sensing indexes, although not developed specifically for wetland delimitation, presented satisfactory results in order to classify these ecosystems. The indexes that showed to be more useful for marshes classification by DT techniques in the study area were NDTI, BI, NDPI and BI_2, with 25.9%, 17.7%, 11.1% and 0.8%, respectively. In general, the Proportion Correct (PC) found was 95.9% and 77.9% for the Summer and Winter images respectively. We hypothetize that this significant PC variation is related to the rice-planting period in the Summer and/or to the water level oscillation period in the Winter. For future studies, we recommend the use of active remote sensors (e.g., radar) and soil maps in addition to the remote sensing spectral indexes in order to obtain better results in the delimitation of small inner marsh areas.[ES] En las últimas décadas se han perdido grandes áreas de pequeñas marismas interiores (SIM) a través de la conversión a tierras agrícolas, urbanas e industriales. Las marismas restantes enfrentan varias amenazas, como el drenaje para la agricultura, la construcción de carreteras e instalaciones portuarias, la eliminación de residuos, entre otras. Este estudio integra 17 índices espectrales de teledetección y un método basado en árboles de decisión (DT) para cartografiar áreas de pequeñas marismas interiores utilizando imágenes del satélite Sentinel 2A de verano e invierno. Los resultados muestran que los índices de teledetección, aunque no han sido desarrollados específicamente para la delimitación de marismas, presentan resultados satisfactorios para clasificar estos ecosistemas. Los índices que demostraron ser más útiles para la clasificación de marismas mediante técnicas de DT en el área de estudio fueron el NDTI, BI, NDPI y BI_2, con 25.9%, 17.7%, 11.1% y 0.8%, respectivamente. En general, la proporción correcta encontrada fue de 95.9% y 77.9% para las imágenes de verano e invierno, respectivamente. Nuestra hipótesis es que esta variación significativa de la proporción correcta está relacionada con el período de siembra del arroz en verano y/o con el período de oscilación del nivel del agua en invierno. Para futuras investigaciones, recomendamos el uso de sensores remotos activos (por ejemplo, radar) y mapas de suelo además de los índices espectrales de teledetección para obtener mejores resultados en la delimitación de pequeñas áreas de marismas interiores.João Paulo Delapasse Simioni thanks the CAPES agency for providing a doctoral fellowship. The au-thors acknowledge the Center for Remote Sensing and Meteorology (CEPSRM) at the Federal University of Rio Grande do Sul (UFRGS) for the support provided for this research.Simioni, JPD.; Guasselli, LA.; Ruiz, LFC.; Nascimento, VF.; De Oliveira, G. (2018). Delimitación de pequeñas marismas interiores mediante índices espectrales y árboles de decisión en el sur de Brasil. Revista de Teledetección. (52):55-66. doi:10.4995/raet.2018.10366SWORD556652Artigas, F. J., Yang, J. 2006. Spectral discrimination of marsh vegetation types in the New Jersey Meadowlands, USA. 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Journal of Spatial Hydrology, 7(2), 62-96. https://doi. org/10.1017/CBO9780511806049Lacaux, J. P., Tourre, Y. M., Vignolles, C., Ndione, J. A., Lafaye, M. 2007. Classification of ponds from highspatial resolution remote sensing: Application to Rift Valley Fever epidemics in Senegal. Remote Sensing of Environment, 106(1), 66-74. https://doi.org/10.1016/j. rse.2006.07.012Leite, M. G., Guasselli, L. A. 2013. Spatio-temporal dynamics of aquatic macrophytes in Banhado Grande, Gravataí River basin,. Para Onde!?, 7(1), 17-24.Liu, L., Liu, Y. H., Liu, C. X., Wang, Z., Dong, J., Zhu, G. F., Huang, X. 2013. Potential effect and accumulation of veterinary antibiotics in Phragmites australis under hydroponic conditions. Ecological Engineering, 53, 138-143. https://doi.org/10.1016/j. ecoleng.2012.12.033Mahdavi, S., Salehi, B., Amani, M., Granger, J. E., Brisco, B., Huang, W., Hanson, A. 2017. ObjectBased Classification of Wetlands in Newfoundland and Labrador Using Multi-Temporal PolSAR Data. 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    Variação fenotípica em populações segregantes de mamoeiro.

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    O mamoeiro (Carica papaya L.) é uma cultura de expressiva importância para o Brasil, um dos principais produtores da fruta, com produção de 1,9 milhão de toneladas em 2008, participando com 20,8% do mercado mundial. Atualmente, há uma tendência de crescimento das exportações brasileiras, iniciada pela abertura do mercado-americano, o que deverá assegurar a estabilidade e maior rentabilidade da cultura (BRAPEX, 2006; ANUÁRIO..., 2010). A ocupação da maior parte dos plantios comerciais por apenas três cultivares tem restringido a variabilidade genética e aumentado a vulnerabilidade da cultura do mamoeiro, ao ataque de pragas e doenças, limitando o seu desenvolvimento. Para dar suporte a essa produção, são desenvolvidos programas de melhoramento visando o desenvolvimento de linhagens, variedades ou híbridos com alta produtividade, boa precocidade de frutificação, porte baixo, resistência às doenças, ocorrência mínima de flores hermafroditas carpelóides, pentândricas e estéreis, elevado teor de sólidos solúveis (> 14o Brix) e padrões de peso cor e firmeza, de acordo com as exigências do mercado. A obtenção de linhagens e híbridos de mamoeiro é favorecida pela possibilidade de o mamoeiro poder ser autopolinizado sem expressiva perda de vigor (DANTAS & LIMA, 2001).pdf 2744 CHAGAS NETO, F., i. e, FRANCISCO DAS CHAGAS VIDAL NET
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